Arrangement in safe walls or the like



SEARCH hUUM March 3, 1964 J. o. FUGELSTAD ARRANGEMENT IN SAFE WALLS OR THE LIKE INVENTOR JOHA/V OSCAR F UGHS T40 Filed Dec. 19, 1960 ATTORNEYS United States Patent 3,123,025 ARRANGEMENT IN SAFE WALLS OR THE LIKE Johan Oscar Fugelstad, Stockholm, Sweden, assignor to Aktiebolaget Platforadling, Halsingborg, Sweden, a corporation of Sweden Filed Dec. 19, 1960, Ser. No. 76,931 6 Claims. (Cl. 10.983)

The present invention refers to an arrangement in safe walls or the like, comprising an outer plate and at least one layer of reinforced concrete, adjacent to said outer plate.

Safes are known, in which a reinforced layer of concrete is utilized to make a burglary more difficult. It is desirable that the reinforcement of the layer of concrete should be relatively compact thereby making the breaking away of the concrete more difficult after the outer plate has been removed. Anchoring the layer of concrete to the outer plate to make cutting away and bending out of said plate more diflicult is also known. However, it is not desirable to make the reinforcement so compact that the concrete filled spaced between the reinforcement elements are so small that concrete is easily broken away at these places. Further, the formation and placement of the reinforcement elements should be such that they do not facilitate the breaking away of concrete.

For achieving a high degree of safety against burglary it is not sufficient to apply inside of an outer plate a reinforcement of any kind, and connect this to the outer plate. For good safety against burglary, the wall must resist working with cutting flame, rotational drill, blowing drill, spit, sledge-hammer and blasting load.

In a safe of the kind here intended, the use of a cutting flame will only be utilized to melt away metal parts, which are available from outside, especially for opening the outer plate in order of making the sheet of concrete under said outer plate available for working with other tools. If one has succeeded in forming a smaller opening in the outer plate, it is further necessary also to break away the outer plate in order to expose the wall parts placed under said outer plate available for further Working. If the breaking away of the outer plate after the cutting of a small hole is made more difficult or even impossible, the time for continuous removal of the outer plate by means of a cutting flame will be prolonged to a high degree. However, in order that a burglary have success, it must be completed in a short space of time.

After breaking up the outer plate, the layer of concrete placed under said outer plate must be worked. From the standpoint of the thief, working with a rotary drill is preferable, because it causes less noise. The working of the concrete, however, will then always be dependent upon the possibility of cracking out the concrete in parts. The more the formation of cracks in the concrete is prevented, the longer will the time be, and more tools will be required for fulfilling the burglary. Also, working with a blowing drill or a sledge-hammer is dependent upon the power of forming cracks in the concrete. Therefore it is important, that the reinforcement is of such a kind that it does not form any breakage points in the concrete mass, and that it is further difficult to reach from the outer side of the wall, and that its destruction in some places will also cause no decrease of the reinforcement effect in the surrounding parts of the wall, and that it will further form a fixture for cramps attached to the outer plate, which is difficult to attach, and, finally, that it has a good combination action with the surrounding concrete, especially the concrete situated between different reinforcement irons as Well as between each of them and the outer plate.

An important condition for a good reinforcement further depends upon the security against fire. It is of great importance that the metal reinforcement shall not form a bridge between the outer plate and the inner plate (or the intermediate plate) and thereby conduct heat directly across the concrete layer. The concrete layer should, under all circumstances, have a heat insulation action. The main heat insulation action may be provided by a second interior layer of material having high insulating characteristics.

This invention refers to an arrangement which achieves the above-mentioned desirable features while simultaneously making the breaking up of the wall very difficult.

While the preceding discussion has been limited to safe-Walls, it is however obvious that the invention is also applicable to other wall elements than those of safes, such as doors or shutters, and that it can also be used in walls or wall parts of other storing rooms.

According to the invention at least one layer of concrete is reinforced by means of a network of reinforcement irons which cross each other and are arranged a distance from the outer plate and run substantially in parallel thereto. The reinforcement irons are anchored to the outer plate by means of strap-likely bent cramp irons, which with their bent intermediate part grip around one or more of the reinforcement irons in the network. Both of the shank ends of the cramp irons are welded to the inner side of the outer plate.

In such safes, where the layer of concrete adjacent to the outer plate is separated from the insulation layer by an intermediate plate, and especially if the insulation layer comprises a relatively hard, moulded insulation mass, a similar reinforcement may be applied also in the insulation layer and may be anchored to the inner side of the intermediate plate in a way similar to the anchoring of the reinforcement irons to the inner side of the outer plate in the concrete layer.

A further reinforcement of the concrete layer against attacks with usual drilling or blowing tools is obtained, in the concrete layer, in addition to the reinforcement, also contains pieces of hardened steel, said pieces forming part of the ballast of the concrete or all of the ballast.

One form of execution is shown in the attached drawing schematically and in section through one part of a safe wall. This comprises an outer plate 1, suitably a steel plate, a sheet of concrete 2 inside thereof, an intermediate plate 3 inside of the sheet of concrete, an insulation layer 4 inside of the intermediate plate, and an inner plate 5, which is suitably augmented by plates 6 of flame hardened steel.

A network of braided reinforcement irons 7 and 8, crossing each other and preferably of round section, is located at approximately the middle of concrete layer 2, said network being placed substantially parallel to the outer plate. The longitudinal (vertical) reinforcement irons 7 as well as the transversal (horizontal) reinforce ment irons 8 are bent slightly zig-zag such that both of them have about the same degree of bending and attach each other where crossed. The vertical series of reinforcement irons 7 is preferably gripped by bent cramp straps 9 where iron 7 is most remote from the outer plate. Cramp straps 9 preferably grip reinforcement irons 7 immediately below the crossing (horizontal) reinforcement irons 8. Cramp straps 9 are preferably of the same bar material as the reinforcement irons, and the shanks of said straps extend to the inner side of the outer plate 1, at which they are fixed by means of welding. It is obvious that straps 9 without any change of their anchoring action may be placed over parts of the transversal (horizontal) reinforcement irons, or that straps may be arranged in a deliberate distribution to grip horizontal and vertical reinforcement irons. The shown arrangement of straps 9 has been chosen for manufacturing-technical reasons, because then they will carry the reinforcement network 7, 8 during the forming of the concrete by supporting the reinforcement irons 8 from below.

The layer of concrete is formed in the space between the outer plate 1 and the intermediate plate 3 after said plates and said reinforcements have been mounted, care being taken by suitable means, such as vibration, and a suitable relation of mixture between cement and water (cement-water-relation suitably less than 0.3), that the layer of concrete will obtain the properties regarding hardness, cohesion, heat resistance, and attraction to the reinforcements and the plates, required for obtaining the highest possible security against burglary and fire.

In addition to the reinforcements anchored to the outer plate, the concrete layer may also contain hardened pieces of steel, which form at least part of the ballast in the mixture of concrete thereby making the concrete very resistant to breaking by usual tools. When the concrete is formed in the above manner, the steel ballast is strongly attached to the concrete.

In the shown form of execution, where the insulation layer 4 is assumed to comprise a relatively hard, moulded mass of good heat insulation and fire resistance, also the insulation sheet is provided with a reinforcement 7a, 8a, which is made and anchored in a similar Way as the reinforcement 7, 8 of the concrete sheet. used to anchor reinforcement irons 7a, 8a to intermediate plate 3.

Other forms of execution than the above described also fall within the scope of the invention. Thus, the reinforcement bars are not braided, but may consist in a grid work of straight bars, mounted to cross each other, said bars at given crossing points being secured by means of a wire binding in a usual way. These bars are not necessarily round in cross-section, as shown, and may have any other suitable cross section. Although very good results may be achieved with these variations, the shown form of execution will give further improved properties relative to the prevention of breakage of the concrete, caused by the arrangement of reinforcement irons. One form of execution, which may be said to form an intermediate between the above mentioned variations and the shown form of execution, may consist in a reinforcement network of reinforcement irons, bent in zigzag form, and braided to parallel, straight reinforcement bars, the reinforcement irons of said first mentioned reinforcement network being of somewhat smaller cross section than said bars and therefore easier to bend.

The anchoring straps are not necessarily V-shaped as shown in the drawing, but may be U-shaped straps or bars bent with one end around the reinforcement bars and the other end of which being welded to the inner plate. The anchoring irons may also grip diagonally over two reinforcement bars at their crossing points. Hookformed anchoring irons may have a hook which surrounds more than half of the circumference of the Clamps 9a are reinforcement bar concerned, in order to keep the reinforcement iron a correct distance from the plate to which it is anchored.

The wall according to the invention may comprise more than one sheet of concrete, for instance one sheet on each side of an insulation layer, if this, due to specific circumstances, should be called for.

What is claimed is:

1. An arrangement in safe walls and the like comprising an outer plate, a plurality of reinforcement irons spaced from the plate and substantially parallel thereto, the irons forming a network wherein said irons cross each other, a plurality of cramp irons, each having two edges and being bent around at least one reinforcement iron, said cramp irons welded to the outer plate by both ends thereof, and a layer of concrete adjacent the outer plate and surrounding the reinforcement irons and the cramp irons.

. 2. An arrangement according to claim 1 wherein the reinforcement irons are interwoven and each iron has a zig-zag bend.

3. An arrangement according to claim 1 wherein the cramp irons are bent around a reinforcement iron substantially at a point where another reinforcement iron crosses between the first-mentioned reinforcement iron and the outer plate.

4. An arrangement according to claim 3 wherein the cramping irons are V-formed and are distributed substantially evenly over the outer plate.

5. An arrangement according to claim 1 and further comprising an intermediate plate adjacent the layer of concrete, additional reinforcement irons and cramp irons arranged in the same manner as the first-mentioned reinforcement irons and cramp irons, wherein the ends of the additional cramp irons are welded to the intermediate plate, and a layer of insulation material adjacent the intermediate plate and surrounding the additional reinforcement irons and cramp irons.

6. An arrangement according to claim 5 wherein the cramp irons are bent around a reinforcement iron substantially at a point where another reinforcement iron crosses between the first-mentioned reinforcement iron and the associated plate.

References Cited in the file of this patent UNITED STATES PATENTS 

1. AN ARRANGEMENT IN SAFE WALLS AND THE LIKE COMPRISING AN OUTER PLATE, A PLURALITY OF REINFORCEMENT IRONS SPACED FROM THE PLATE AND SUBSTANTIALLY PARALLEL THERETO, THE IRONS FORMING A NETWORK WHEREIN SAID IRONS CROSS EACH OTHER, A PLURALITY OF CRAMP IRONS, EACH HAVING TWO EDGES AND BEING BENT AROUND AT LEAST ONE REINFORCEMENT IRON, SAID CRAMP IRONS WELDED TO THE OUTER PLATE BY BOTH ENDS THEREOF, AND A LAYER OF CONCRETE ADJACENT THE OUTER PLATE AND SURROUNDING THE REINFORCEMENT IRONS AND THE CRAMP IRONS. 